Your role Rachel Weisz. Too pretty to be me, but otherwise seems to fit.
Lover One Richard Gere or Pierce Brosnan for bardiphouka. Problem being Gere is too American and looks older than he is sometimes (I think it's the hair), and Brosnan is too well spoken. Though quite tasty. Not sure either of them would suit long hair.
Lover Two can be a second lover or an ex Ioan Gruffudd (the guy who plays Hornblower on TV, yes the nice Welsh lad) to play a fellow by the name of Colin, but Ioan is much better looking. To give you an idea of the character, on our first real date I sat in the police station for an hour or so while he went to see his parole officer.
Best/Ex Friend Lisa Faulkner to play the frequently mentioned Hay. No real reason other than they're both blonde and British, and Falkner is not a bad actress.
bad guy/woman Joseph Fiennes to play Lee. He's seems like a really great guy for a while, then completely surprises the audience by actually turning out to be a horrible person. Pretty much the way it happened.
Other Important Roles Alyson Hannigan for ramothhe (Hannigan is good at playing sweet redheads with a wicked sense of humour), Seth Green for neochichiri (really if you know him this needs no explainations), Vince Vieluf for neosuboshi (though I did actually seriously contemplate Wil Wheaton, but went with Vieluf because I saw him Playing Seth Green's brother in Rat Race and they seemed to work nicely), Jude Law to play my brother (they seem quite alike some ways, and I really like Jude Law).
I'd also add the Producer and screenwriter but i don't know about these things, and I'm not putting in the comic relief because I'm pretty sure that will come from the last category of cast ;)
That was hard to do.